This is a proposal for partial funding of a Gordon Research Conference on Muscle: Excitation-Contraction (E-C) Coupling to be held in June 2003. E-C coupling is the process that translates a muscle action potential into an increase in [Ca2+]i and contraction. Recent advances have brought into sharp focus the necessity of understanding the molecular events that underlie E-C coupling, in particular, the interaction between the two intramembrane molecules that are key to E-C coupling, the sarcoplasmic reticulum Ca2+ release channel or ryanodine receptor (RyR) and the transverse tubule voltage sensor or dihydropyridine receptor (DHPR). The meeting will bring together specialists in membrane protein structure, human genetics, molecular biology, biochemistry, biophysics and physiology to discuss the approaches that will advance molecular understanding of Ca2+ signaling in skeletal muscle, with implications for other tissues. The problems considered by this diverse group will range from molecular structure through the physiological results of molecular manipulation and modification of the key proteins underlying muscle activation. The meeting will focus discussion on several key aspects of Ca2+ signaling in skeletal muscle in nine platform sessions: (1) cellular organization and molecular structures of key proteins; (2) molecular interactions between DHPR and RyR; (3) molecular basis and pathophysiology of inherited muscle diseases caused by defects in E-C coupling proteins; (4) elementary events of Ca2+ release; (5) accessory protein and biochemical modulation of RyR function; (6) molecular manipulation and expression of E-C coupling components; (7) global calcium transients and fatigue in muscle fibers; (8) excitation transcription coupling in muscle and other cells; (9) other Ca2+ pathways in muscle. Posters will be shown continuously. The Gordon Conference on Muscle: E-C coupling, held every three years for several decades, has consistently been the sole forum in which active investigators from all over the world are brought together for discussion and dissemination of ideas that have led to advances in this field. The format encourages free exchange of ideas and unpublished data. The organizing committee and session leaders will strive to achieve appropriate representation of women, minorities and disabled. All facilities are handicapped accessible.